DOI： 10.5194/egusphere-2023-197-supplement

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

Visualization of dust flow and wind dynamics near the ground surface are essential for understanding the mixing and interaction between geosphere and atmosphere near the surface. Knowing the temporal dust flow is beneficial in dealing with air pollution and health issues. Dust flows near the ground surface are difficult to monitor because of their small temporal and spatial scale. In this study, we propose a low-coherence Doppler lidar (LCDL) for measuring dust flow near the ground with high temporal and spatial resolutions of 5 ms and 1 m, respectively. We demonstrate the performance of LCDL in laboratory experiments using flour and calcium carbonate particles released into the wind tunnel. LCDL experiment results show a good agreement with anemometer measurement in wind speeds ranging from 0 to 5 m/s. The LCDL technique can reveal dust’s speed distribution, which is affected by mass and particle size. As a result, different speed distribution profiles can be used to determine dust type. The simulation results of dust flow coincide well with the experimental results.

DOI： 10.1038/s41598-023-30346-z

Web of Science

researchmap

Other Link： https://www.nature.com/articles/s41598-023-30346-z

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3390/photonics10020146

Publishing type：Research paper (international conference proceedings)   Publisher：SCITEPRESS  

DOI： 10.5220/0011677400003408

researchmap

Other Link： https://dblp.uni-trier.de/db/conf/photoptics/photoptics2023.html#HuyanLS23

Language：English   Publishing type：Research paper (scientific journal)   Publisher：{AIP} Publishing  

When the conventional optical coherence tomography (OCT) measures the transmittance and the absorbance of the target in the scattering media, its image is affected by the scattering media and gets a modulated target profile. Due to the influence of scattering and absorption by the media, the conventional OCT cannot eliminate this modulation. By using our proposed idea, ghost imaging-OCT (GI-OCT), to apply the GI technique to the measurement path of OCT, we can reconstruct the target profile in the scattering media without modulation. In this work, we introduce and demonstrate the concept and the experimental method of GI-OCT. This application can correct the influence of the scattering media for the target optical profile due to the advantage of the GI technique, which suppresses noise, here, modulated by scattering. Comparing the experimental results of the corrected target image with the original target image, we obtain the same distributions in the binarized images, and the error of the character size in the binarized deconvoluted image is less than the resolution of the image (0.04 mm), proving that the method successfully reconstructs the image without the scattering media influence.

DOI： 10.1063/5.0099638

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1038/s41598-022-12810-4

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI  

Comparing cloud cover (CC) products from different satellites with the same ground-based CC dataset provides information on the similarities or differences of values among satellite products. For this reason, 42-month CC products from Moderate Resolution Imaging Spectrometer's (MODIS) Collection 6.1 daily cloud cover products (MOD06_L2, MYD06_L2, MOD08_D3, and MYD08_D3) and Himawari-8 are compared with the ground-based camera datasets. The comparison shows that CC from MODIS differs from ground measurement CC by as much as 57% over Chiba, Japan, when low CC is observed by the camera. This indicates MODIS's ability to capture high-level clouds that are not effectively seen from the ground. When the camera detects high CC, an indication of the presence of low-level clouds, CC from MODIS is relatively higher than the CC from the camera. In the case of Himawari-8 data, when the camera observes low CC, this difference is around 0.7%. This result indicates that high-level clouds are not effectively observed, but the Himawari-8 data correlates well with camera observations. When the camera observes high CC, Himawari-8-derived CC is lower by around 10% than CC from the camera. These results show the potential of continuous observations of nighttime clouds using the camera to provide a dataset that can be used for intercomparison among nighttime satellite CC products.

DOI： 10.3390/rs14040960

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3390/rs14040960

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1029/2021JD034772

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1038/s41598-020-78789-y

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1364/AO.398673

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.5194/acp-20-1255-2020

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3390/atmos11010036

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.3390/rs11242944

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.4209/aaqr.2018.07.0267

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1021/acs.est.8b01658

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.4236/ars.2018.73013

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.4236/ars.2018.73015

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1080/01431161.2018.1475776

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.4236/ojap.2018.72008

Language：English   Publishing type：Research paper (scientific journal)  

Ship-based measurements of aerosol and cloud condensation nuclei (CCN) properties are presented for 2 weeks of observations in remote marine regions of the South China Sea/East Sea during the southwestern monsoon (SWM) season. Smoke from extensive biomass burning throughout the Maritime Continent advected into this region during the SWM, where it was mixed with anthropogenic continental pollution and emissions from heavy shipping activities. Eight aerosol types were identified using a k-means cluster analysis with data from a size-resolved CCN characterization system. Interpretation of the clusters was supplemented by additional onboard aerosol and meteorological measurements, satellite, and model products for the region. A typical bimodal marine boundary layer background aerosol population was identified and observed mixing with accumulation mode aerosol from other sources, primarily smoke from fires in Borneo and Sumatra. Hygroscopicity was assessed using the κ parameter and was found to average 0.40 for samples dominated by aged accumulation mode smoke; 0.65 for accumulation mode marine aerosol; 0.60 in an anthropogenic aerosol plume; and 0.22 during a short period that was characterized by elevated levels of volatile organic compounds not associated with biomass burning impacts. As a special subset of the background marine aerosol, clean air masses substantially scrubbed of particles were observed following heavy precipitation or the passage of squall lines, with changes in observed aerosol properties occurring on the order of minutes. Average CN number concentrations, size distributions, and κ values are reported for each population type, along with CCN number concentrations for particles that activated at supersaturations between 0.14 and 0.85 %.

DOI： https://doi.org/10.5194/acp-17-1105-2017

Language：English   Publishing type：Research paper (scientific journal)  

The largest 7 Southeast Asian Studies (7SEAS) operation period within the Maritime Continent (MC) occurred in the August–September 2012 biomass burning season. Included was an enhanced deployment of Aerosol Robotic Network (AERONET) sun photometers, multiple lidars, and field measurements to observe transported smoke and pollution as it left the MC and entered the southwest monsoon trough. Here we describe the nature of the overall 2012 southwest monsoon (SWM) and biomass burning season to give context to the 2012 deployment. The MC in 2012 was in a slightly warm El Niño/Southern Oscillation (ENSO) phase and with spatially typical burning activity. However, overall fire counts for 2012 were 10 % lower than the Reid et al. (2012) baseline, with regions of significant departures from this norm, ranging from southern Sumatra (+30 %) to southern Kalimantan (−42 %). Fire activity and monsoonal flows for the dominant burning regions were modulated by a series of intraseasonal oscillation events (e.g., Madden–Julian Oscillation, or MJO, and boreal summer intraseasonal oscillation, or BSISO). As is typical, fire activity systematically progressed eastward over time, starting with central Sumatran fire activity in June related to a moderately strong MJO event which brought drier air from the Indian Ocean aloft and enhanced monsoonal flow. Further burning in Sumatra and Kalimantan Borneo occurred in a series of significant events from early August to a peak in the first week of October, ending when the monsoon started to migrate back to its wintertime northeastern flow conditions in mid-October. Significant monsoonal enhancements and flow reversals collinear with tropical cyclone (TC) activity and easterly waves were also observed. Islands of the eastern MC, including Sulawesi, Java, and Timor, showed less sensitivity to monsoonal variation, with slowly increasing fire activity that also peaked in early October but lingered into November. Interestingly, even though fire counts were middling, resultant AERONET 500 nm aerosol optical thickness (AOT) from fire activity was high, with maximums of 3.6 and 5.6 in the Sumatra and Kalimantan source regions at the end of the burning season and an average of ∼ 1. AOTs could also be high at receptor sites, with a mean and maximum of 0.57 and 1.24 in Singapore and 0.61 and 0.8 in Kuching Sarawak. Ultimately, outside of the extreme 2015 El Niño event, average AERONET AOT values were higher than any other time since sites were established. Thus, while satellite fire data, models, and AERONET all qualitatively agree on the nature of smoke production and transport, the MC's complex environment resulted in clear differences in quantitative interpretation of these datasets.

DOI： https://doi.org/10.5194/acp-16-14041-2016

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.5194/acp-16-9629-2016, 2016

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1364/AO.55.006040

Language：English   Publishing type：Research paper (scientific journal)  

The largest 7 Southeast Asian Studies (7SEAS) operations period within the Maritime Continent (MC) occurred in the August–September 2012 biomass burning season. Data included were observations aboard the M/Y Vasco, dispatched to the Palawan Archipelago and Sulu Sea of the Philippines for September 2012. At these locations, the Vasco observed MC smoke and pollution entering the southwest monsoon (SWM) monsoonal trough. Here we describe the research cruise findings and the finer-scale aerosol meteorology of this convectively active region. This 2012 cruise complemented a 2-week cruise in 2011 and was generally consistent with previous findings in terms of how smoke emission and transport related to monsoonal flows, tropical cyclones (TC), and the covariance between smoke transport events and the atmosphere's thermodynamic structure. Biomass burning plumes were usually mixed with significant amounts of anthropogenic pollution. Also key to aerosol behavior were squall lines and cold pools propagating across the South China Sea (SCS) and scavenging aerosol particles in their path. However, the 2012 cruise showed much higher modulation in aerosol frequency than its 2011 counterpart. Whereas in 2011 large synoptic-scale aerosol events transported high concentrations of smoke into the Philippines over days, in 2012 measured aerosol events exhibited a much shorter-term variation, sometimes only 3–12 h. Strong monsoonal flow reversals were also experienced in 2012. Nucleation events in cleaner and polluted conditions, as well as in urban plumes, were observed. Perhaps most interestingly, several cases of squall lines preceding major aerosol events were observed, as opposed to 2011 observations where these lines largely scavenged aerosol particles from the marine boundary layer. Combined, these observations indicate pockets of high and low particle counts that are not uncommon in the region. These perturbations are difficult to observe by satellite and very difficult to model. Indeed, the Navy Aerosol Analysis and Prediction System (NAAPS) simulations captured longer period aerosol events quite well but largely failed to capture the timing of high-frequency phenomena. Ultimately, the research findings of these cruises demonstrate the real world challenges of satellite-based missions, significant aerosol life cycle questions such as those the future Aerosol/Clouds/Ecosystems (ACE) will investigate, and the importance of small-scale phenomena such as sea breezes, squall lines, and nucleation events embedded within SWM patterns in dominating aerosol life cycle and potential relationships to clouds.

DOI： https://doi.org/10.5194/acp-16-14057-2016

Language：English   Publishing type：Research paper (scientific journal)  

In a joint NRL/Manila Observatory mission, as part of the Seven SouthEast Asian Studies program (7-SEAS), a 2-week, late September 2011 research cruise in the northern Palawan archipelago was undertaken to observe the nature of southwest monsoonal aerosol particles in the South China Sea/East Sea (SCS/ES) and Sulu Sea region. Previous analyses suggested this region as a receptor for biomass burning from Borneo and Sumatra for boundary layer air entering the monsoonal trough. Anthropogenic pollution and biofuel emissions are also ubiquitous, as is heavy shipping traffic. Here, we provide an overview of the regional environment during the cruise, a time series of key aerosol and meteorological parameters, and their interrelationships. Overall, this cruise provides a narrative of the processes that control regional aerosol loadings and their possible feedbacks with clouds and precipitation. While 2011 was a moderate El Niño–Southern Oscillation (ENSO) La Niña year, higher burning activity and lower precipitation was more typical of neutral conditions. The large-scale aerosol environment was modulated by the Madden–Julian Oscillation (MJO) and its associated tropical cyclone (TC) activity in a manner consistent with the conceptual analysis performed by Reid et al. (2012). Advancement of the MJO from phase 3 to 6 with accompanying cyclogenesis during the cruise period strengthened flow patterns in the SCS/ES that modulated aerosol life cycle. TC inflow arms of significant convection sometimes span from Sumatra to Luzon, resulting in very low particle concentrations (minimum condensation nuclei CN < 150 cm−3, non-sea-salt PM2.5 < 1 μg m−3). However, elevated carbon monoxide levels were occasionally observed suggesting passage of polluted air masses whose aerosol particles had been rained out. Conversely, two drier periods occurred with higher aerosol particle concentrations originating from Borneo and Southern Sumatra (CN > 3000 cm−3 and non-sea-salt PM2.5 10–25 μg m−3). These cases corresponded with two different mechanisms of convection suppression: lower free-tropospheric dry-air intrusion from the Indian Ocean, and large-scale TC-induced subsidence. Veering vertical wind shear also resulted in aerosol transport into this region being mainly in the marine boundary layer (MBL), although lower free troposphere transport was possible on the western sides of Sumatra and Borneo. At the hourly time scale, particle concentrations were observed to be modulated by integer factors through convection and associated cold pools. Geostationary satellite observations suggest that convection often takes the form of squall lines, which are bowed up to 500 km across the monsoonal flow and 50 km wide. These squall lines, initiated by cold pools from large thunderstorms and likely sustained by a veering vertical wind shear and aforementioned mid-troposphere dry layers, propagated over 1500 km across the entirety of the SCS/ES, effectively cutting large swaths of MBL aerosol particles out of the region. Our conclusion is that while large-scale flow patterns are very important in modulating convection, and hence in allowing long-range transport of smoke and pollution, more short-lived phenomena can modulate cloud condensation nuclei (CCN) concentrations in the region, resulting in pockets of clean and polluted MBL air. This will no doubt complicate large scale comparisons of aerosol–cloud interaction.

DOI： https://doi.org/10.5194/acp-15-1745-2015

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.5194/amt-8-505-2015

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.atmosres.2012.06.005

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1007/s00376-006-0461-z

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1088/1009-1963/14/11/037

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.jaerosci.2004.10.007

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.atmosenv.2004.02.060

Event date： 2023.12

Language：English  

Country：United States  

Other Link： https://agu.confex.com/agu/fm23/meetingapp.cgi/Paper/1379430

Event date： 2023.12

Language：English  

Country：United States  

Event date： 2023.11

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.9

Language：English  

Country：Netherlands  

Event date： 2023.9

Language：English   Presentation type：Oral presentation (general)  

Country：Netherlands  

Event date： 2023.2

Language：English  

Country：Portugal  

Event date： 2022.12

Language：English  

Country：United States  

Event date： 2022.6 - 2022.7

Language：English  

Country：United States  

Other Link： https://link.springer.com/search?query=lagrosas&facet-eisbn=978-3-031-37818-8&facet-content-type=Chapter

Event date： 2022.6 - 2022.7

Language：English  

Country：United States  

Other Link： https://link.springer.com/search?query=lagrosas&facet-eisbn=978-3-031-37818-8&facet-content-type=Chapter

Event date： 2022.6 - 2022.7

Language：English  

Country：United States  

Other Link： https://link.springer.com/search?query=lagrosas&facet-eisbn=978-3-031-37818-8&facet-content-type=Chapter

Event date： 2022.6 - 2022.7

Language：English  

Country：United States  

Other Link： https://link.springer.com/search?query=lagrosas&facet-eisbn=978-3-031-37818-8&facet-content-type=Chapter

Event date： 2022.2

Language：Japanese   Presentation type：Poster presentation  

Venue：オンライン   Country：Japan  

Event date： 2021.12

Language：English  

Country：United States  

Event date： 2021.12

Language：English   Presentation type：Oral presentation (general)  

Country：United States  

Event date： 2021.11

Language：English  

Country：Other  

Event date： 2021.11

Language：English  

Country：Japan  

Event date： 2021.11

Language：English  

Country：Other  

Event date： 2021.11

Language：English  

Country：Other  

Event date： 2021.11

Language：English  

Country：Other  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：online   Country：Japan  

Other Link： https://laser-sensing.jp/lss39/lss39_program.pdf

Event date： 2021.3

Language：Japanese  

Country：Japan  

Event date： 2020.12

Language：English  

Country：Other  

Event date： 2019.12

Language：English  

Country：United States  

Event date： 2019.11

Language：English  

Country：Japan  

Type：Academic society, research group, etc.